Eternity
by 12345eater
Summary: When the Queen of the Nightosphere(a.k.a Marshall's mother) is trying to bring Marshall back to the Nightsphere, it's up to Fionna to save him. What will she have to do to save him? What will she lose?
1. Chapter 1

**Author's note: Hey there, I'm 12345eater or Emily, but to let you know this will be a fanfic about Marshall Lee and Fionna. There will be some fluff later on, so if you don't want that this isn't the right fanfic for you. Anyways this is my first fanfic I'm posting online so please leave reviews about what I could do better on. I only ask that you're nice about it. So please enjoy the first chapter!**

1

Fionna

"Fionna?" she heard Cake call from in the living room. It was quite at the treehouse surprisingly, and she was enjoying it. It seemed every moment of her life she was running to chase after monsters and whatnot. Today was their day off. She was making popcorn currently, one of her favorite snacks. Cake preferred sweet things, like well cake. "Are you done with the snacks? I'm getting mighty bored waiting for you."

"Yeah, yeah I'm coming." she said as she walked into the living room. She plopped down into the recliner with her bowl of popcorn. Cake curled up into her lap, she was a cat after all.

"So I've been thinking you should ask Gumball out. It's been forever since you and Flame Prince broke up. Fionna you need a man in your life. Just look at me and Lord Monochromicorn, we are very happy and you need that kinda happiness in your life." Cake said, with lots of sass in her voice.

"I don't see why I need a boyfriend. It's not going to help me kill monsters is it? Besides Gumball isn't very fun is he? Don't get me wrong, he's a great friend, but I need someone more exciting. Kinda like Mar-" she began.

"Marshall Lee! I knew it! You like him, don't you?" Cake was practically purring. "I can see it now, the Vampire King and his new bride, the adventurist Fionna. Can I be you Maid of Honor?"

"I never said anything like that! I was just using him as an example!" Fionna yelled. "You're taking this the wrong way! Anyways even if I did like him, I would never ask him out. He's royalty, and I've learned my lesson with that."

"Fionna one bad experience doesn't mean you should give up the dating royals. I don't even think you could call Marshall royal, I mean he doesn't have that many subjects does he?" Cake said.

"I actually have more than you would think. They're not as nearly as mean as me though. Picture them as cute puppies and me as a vicious bull dog. And I'm not just any royalty am I? I'm a king and don't you forget it." said a voice behind them. Cake jumped out of her lap and into the air, hissing in surprise. Fionna went to elbow the perpetrator, but he was already in the air, laughing.

"What the glob are you doing here Marshall?!" she yelled. "I never said you could come over!"

Marshall's face changed from its normal cocky look, to a more serious look. He got a tighter grip on his base axe. "Fine I'll get right to the point. I need your help, and I need it now." So much for their peaceful evening.


	2. Chapter 2

**Author's note: A lot of people liked the first chapter, so thanks for that. The problem was that the chapter was really short. I'm going to work on making chapters longer. I think that one was short, because I really suck at writing first chapters. It's really hard for me to start stories, but as I continue writing, I the chapters get longer. Anyways this chapter is in Marshall's POV. Hope you enjoy.**

2

Marshall

"What is it you need help with Marshall?" Fionna asked, getting annoyed. They were walking (well he was floating, but what did that matter?), in the direction of his house. They were ready for battle, Fionna with her crystal sword and Cake's stretching powers.

"Well my mother may or may not be coming to my house right now to take me back to the Nightosphere. You know it's always a big if with her. If she is coming, I won't be able to fight her alone, so that's where you come in." he said casually, trying to sound like he wasn't freaking out.

"You've got to be kidding me. How the glob are we going to be able to fight the Queen of the Nightosphere. Do you think we have a death wish?" Cake said. She looked agitated. He guessed he would be to if they had asked him to go up against someone extremely powerful.

"We don't have to fight her to the death or anything, you just have to buy time while I through her back into the Nightosphere. It's very simple. Just distract her for a bit, and don't get your souls taken." he said, but his argument probably sounded crappy. He was just hoping they would help him because they're his friend and they don't want him to be kidnapped.

"Ok, we'll do it." Fionna said. "But you have to promise if anything gets to bad we'll run, all of us, and get to a safe place to rest." She looked protectively at Cake and then, to his surprise, she gave the same look to him. He knew then that Fionna would do anything to protect Cake and him, and that he was right in asking for her help.

"I promise." he said, giving the same look back to them.

They were almost at his house when the smell hit him. It smelt like something was rotting. A smell very common in the Nightosphere. "She's already here." he said. Looking down at Fionna and Cake he saw they were ready for what was to come. The harsh look in their eyes said it all. Looking at his house, he saw that nothing had changed since he left.

"I don't think she's here yet." Fionna said.

"No, she is. This is just how she likes to do things." he replied. The three walked into the house to see a woman sitting on the couch. She was tall, with black hair that went down to her waist. Her eyes were red, but unlike his bright color of red, hers was the color of blood.

"Now, Marshall, we can do this the easy way or the hard way. The hard way, might I add, is the way were you two friends get killed. Make your decision." she said.

Before he could speak, Fionna cut in, "Now look, lady or Queen or whatever, I don't plan on dying tonight, so you might as well just leave."

"Have more respect. I rule the underworld. I am Hannah Abadeer. So little girl, what do you say to that?" Hannah said.

"You're evil, and you want to kidnap Marshall, so I will fight you." Fionna said. Gosh, how did this girl have so much courage? Or maybe it was stupidity, but that didn't matter. The determination on her face made her the most beautiful person in Aaa.

"I'm not going with you, I'm staying here." he finally said. His mother's face changed from irritation to rage.

"Have it your way Marshall." Hannah said, as she attacked Fionna. Fionna was fast, but she wouldn't be able to dodge fast enough. He quickly plunged his axe into her arm, before any damage to Fionna could be done. Hannah screamed, and slapped Marshall across the face and slamming him against the wall.

Fionna quickly attacked, stabbing Hannah in the shoulder. Hannah threw her off, and she would have gotten seriously hurt if Cake wasn't there to catch her. After setting Fionna down, Cake jumped onto Hannah, clawing at her face. Hannah ripped Cake off of her and just when he was about to attack in Cake's place, Hannah hit him in the head, sending him into darkness.


	3. Chapter 3

**Authors note: So this chapter was hard to write. I'm still not sure that I like it all that much, but I guess its ok. I didn't have much inspiration to write it, so I ended up writing it over the week. Anyways I hope you enjoy.**

3

Fionna

In awe, she saw Marshall fall into Hannah's arms. "Since you're a friend of Marshall's, I won't kill you. I will be leaving now that I have him." Hannah said.

"No! Please wait!" Fionna yelled. She jumped and rapped her arms around Hannah's waist. She couldn't let Hannah take Marshall. Marshall belonged in this world, with her. She couldn't lose him. She just couldn't.

"Get off of me, child!" Hannah said, throwing her up against a wall. "What makes you think that you can touch me?"

"Please! I'll do anything as long as Marshall can stay here!" Fionna said. She hoped that her voice sounded strong, although she probably looked like she was just a child.

"You would make a deal with the queen of evil, to keep Marshall here?" Hannah asked, curiosity filling her voice.

"Fionna, watch it." Cake said. Cake was worried about her, but right now all that mattered was keeping Marshall here.

"Yes! Yes, what do you want? As long as Marshall can stay here with me I'll do anything." she said, this time knowing that her voice sounded strong.

"Then that's it." Hannah said. "If you want Marshall to stay here then you must stay with him forever. The longest you may stay away from him is a week. If you stay away longer then a week, he will be brought back to the Nightosphere. It will be like that forever."

"But I'm not immortal." she said.

"Who do you think I am? I can easily make you immortal. I'll make your cat immortal too." Hannah said.

"Can you give me some time to talk with Cake before I answer? I want to make sure it's ok with her." she asked.

"You have an hour." Hannah said, and with that she was gone.

* * *

><p>"Oh Fionna, what have you gotten us into?" Cake asked. She was still on the ground. Cake wrapped her arms around her. She leaned into the furry feline, close to tears.<p>

"I'm sorry Cake. I have to do this, though. I didn't protect Marshall when I should have. I need to save him now." she said.

"Fionna, just face it, you're in love with Marshall. Besides, I think it's for the best. Everyone else is immortal here. Just think of it this way, we get to spend time with our friends forever now." Cake said, hugging her tighter.

"I do love Marshall. I love him a lot, but I don't think I could be with Marshall because of what happened with Flame Prince." she said. The tears were really coming close to tears now. She begged them to stay inside.

"Not everyone will be like Flame Prince. He's not going to betray you like Flame Prince is. You can trust Marshall. He may be the king of the vampires, but my cat feelings make me believe he's good for you. You need to let Flame Prince go." Cake said. The tears finally streamed down her face. She knew Cake was right. It was time to move on. First things first though, she had to prepare to face Hannah again.

After an hour of asking Cake if she looked tough, Hannah finally came back. Marshall was behind her, awake. He was in chains, but not normal ones. These ones were covered on enchantments. Looking closer at Marshall, she saw that he looked exhausted. The enchantments were draining his strength. "Fionna what did you do?" he asked.

* * *

><p>"I have an answer for you Hannah." she said, completely ignoring Marshall. She was looking at Hannah, hoping Hannah could see the hatred in her eyes.<p>

"What is your decision?" Hannah asked, smiling in her anger.

"I'll do it." she said.

"Fionna what are you giving up?" Marshall asked. "I don't want you to get hurt just to keep me here."

"Then it is done." Hannah said. She was also ignoring Marshall. She pointed at Cake first, and with a gasp, Cake fell to the ground. She was about to rush over to Cake, when Hannah pointed at her. She felt a sudden pain. She fell to the ground. It felt like every one of her cells were dying, but within a second, she didn't feel the pain anymore. She looked up at Hannah, who was laughing. "See you in an eternity." With that Hannah left, leaving the three of them behind.

"Fionna, what did you do?" Marshall asked, rushing over to her. He didn't have the chains on anymore, but he still looked tired.

"In order to keep you in this world, I had to stay with you forever. Hannah made Cake and me immortal. If I leave you for more than a week, then you will be pulled back into the Nightosphere." she said, gasping. She was still sore from Hannah's spell.

"Why?" he asked, falling on his knees next to her. "You're lucky that you didn't have to give up more. You shouldn't have done it."

"You're saying that is shouldn't have saved you?" she asked.

"Not if it meant making a deal with Hannah. You should have left me there." Marshall said.

"I couldn't have done that." she said.

"Why? Why couldn't you have just left me there?" Marshall asked, almost yelling.

"Because I love you. I couldn't have just left you there, knowing that I could have helped you." she said.

Marshall looked at her in shock. "You what?" he asked. "Did you just say that you loved me?" She nodded. He reached over and pulled her to him. He wrapped her arms around her and squeezed. "Well, I think I love you too. It's just a guess, though." Marshall said, sounding very cocky. "Anyways, it looks like I'm staying at your place, considering that my house is in ruins."

"I guess that's fine." said Cake from behind them. "Just don't make a mess of my house or I'll be all over you like butter on bread. Come on let's get back, it'll be sunrise soon."

She and Marshall stood up together, and walked out of the house, ready for a new life.

**Just a quick note, this is not the end. I will be doing more chapters, and I already have lots of ideas. I would show them, but you know, I don't want to put in any spoilers. *Insert picture of River Song.* See you guys in the next chapter!**


	4. Chapter 4

**Author's note: This chapter took forever to write. I got half way through it and then restarted countless times. I still don't think I'm completely pleased with it, but I still think it's really nice. It shows a lot of Marshall's feelings about Fionna. And this story will go back to getting an update every Friday. This is being put up early because I was able to work on it all day today, when usually only have under an hour a day to write. One last thing. I think I'm going to do a special Halloween 2 part story, so tell me what you think about that.**

4

Marshall

Fionna was asleep next to him. He was still trying to figure out if she really loved him or not. He loved her, and he had for a while, but what about her. She didn't tell him anything. He didn't know anything about her human family, all though he had heard about her meeting her mother. He didn't know what exactly happened, so all he could do was assume it was a good meeting. She knew most of what happened to him, like his past with the Ice Queen, and his crazy ex Ashley. He really didn't know anything about her past relationships, except that she and Flame Prince had gone up. So did she really love him, or was she just pretending to keep him from getting stuck in the Nightosphere. But if that was true, then why did she want him to stay in Aaa in the first place?

Shaking these thoughts from his head, he got out of bed. It was about 9:00pm. Fionna had switched her sleep schedule, so that she could spend more time with him, but today was different. There was an emergency call from the Candy Kingdom and she had to go help. He wanted to go with her and Cake, but what good would he do in the sunlight?

He floated downstairs to make breakfast for Fionna. Cake was currently at Lord Monochromicorn's house, so he didn't have to worry about making her breakfast too. He was just going to have strawberries, his favorite source of red. Well, second favorite. Blood was obviously his first choice, but wasn't that true for all vampires?

Looking in the fridge, he saw there wasn't much to work with. They would have to go shopping at the Candy Kingdom soon. At least there was some pancake mix. Pancakes are Fionna's favorite food.

He was just about to start, when there was a knock on the door. He floated down to the treasure room to answer the door. When he opened it he saw there was a tall blond woman outside of it. She was wearing red, and had the same figure as Fionna. Looking closer he saw many similarities between her and Fionna. The woman was swaying, obviously drunk. Seeing him, she stood up straight. "Hey there hot stuff." she said. She was obviously flirting with him, and it was weird. Yes, he was hundreds of years older than her, but he didn't look it and she didn't know that. "I'm looking for my Fionna the human, do you know where she lives?" Her breath smelled heavily like alcohol, and he thought he was going to puke.

"And who are you?" he asked. She may be creeping him out a bit, but he had to know whether she was going to hurt Fionna or not. She may not really love him, but he sure loved her and he would die to protect her.

"You can't tell? I am Martha the human, Fionna's mother. I'm sure you know my daughter, she is rather famous, isn't she?" Martha said. That's why Martha and Fionna looked so familiar. They were related. He might as well let her in then. Fionna would probably be happy to see her mother, even though she was a little drunk.

"I guess you can come in." he said. "I was making some breakfast for her, but I guess I could make some for you too."

"She lives here? With you?" Martha asked. Apparently Fionna had not told her mother about him.

"Yeah, I'm her boyfriend. Are you going to come in or not?" he asked. He immediately regretted it though. Sometimes he wished that he wasn't so rude, especially when he was making a first impression on his girlfriend's mother. She didn't seem to mind though.

The front door was in the treasure room, so they had to walk through it. Martha stared at all of the treasure. "She has all this money?" Martha asked. He nodded. "One last question. Why are you eating breakfast this late at night?"

"Oh, I'm a vampire. The Vampire King, actually." he said.

"My daughter has quite the nice life, huh." Martha said.

"She's gone through a lot to get here, and she never leave's anyone behind." he said. "That's why I'm with her. She's strong, and she's different than other girls."

"She gets it from her mother." Martha said. Back in the kitchen he started back on breakfast. "Unlike you too, I sleep during the night. I really don't want that bad of a hangover tomorrow, so I'm going to sleep on the couch." Then off she went.

He didn't really know what to think about Fionna's mother. She looked like she was bad news, but who knows. "WHAT ARE YOU DOING HERE!?" Fionna yelled. He rushed into the living room. Inside he saw Fionna had her mother by the neck. He pulled Fionna off of Martha before it could go any farther. "Why is she here Marshall?"

"She knocked on the door. She's your mother isn't she? Don't you want to see her?" he asked.

"Of course she does." Martha said.

"Why would I ever want to see you?! You're a dead-beat and you've never done anything but hurt me!" Fionna yelled jumping out of his arms and running upstairs.

"Might as well go after her. I'll be here in the morning." Martha said.

"Don't count on it." he said, running after Fionna.

**Look at that. A cliffhanger. Awesome right. Next update will be next Friday! See you then!**


	5. Chapter 5

**Authors note: This is a day late. I'm sorry. I didn't intend for it to happen. Anyways this is kind of a boring chapter, but the next chapter will be faster paced. And the next chapter will be in November. I'm going to do a two part story for Halloween. So this won't be updated for a while. Anyways the chapter is waiting, so enjoy.**

5

Fionna

She already had her sword when Marshall had gotten there. She was about to walk around him when he grabbed her arm. "Fionna, what's wrong? Actually don't answer that. I know hatred when I see it. Why do you hate her? What did you mother do to you?" he asked.

"It's a long story." she said.

"We have time." Marshall said, putting his arm around her. She immediately felt calmer, and more focused. She did love how he was there for her. He was a constant factor in her crazy life. She needed to confide in him more, but it was hard. She could tell it was hurting him that she did keep a lot about her past from him, but there was so much only her and Cake knew. They had kept it a secret, but Marshall wasn't going anywhere anytime soon so she should start telling him. She would start with what happened between her and her mother, than she would go on to tell him what happened with Flame Prince.

"It happened a few months ago, after Flame Prince and I broke up." She began. "Do you know who Beatrice is?"

"Yeah the famous hero who beat the Lich." he answered.

She nodded, then continued. "I knew her before she died. Her ex-boyfriend and I found her bucket list and long story short I found out that my mother was alive. Cake and I went on a quest to find her. She was in a jail. I got her out of her cell. She used me to get out and then left me. She's a deadbeat and she needs to leave me alone. She needs to get out of my house."

She was shaking when she finished, trying to hold back tears. Marshall's grip got tighter. He soon said, "What does she want?"

"Money, power, minions. What doesn't she want is the question." she answered.

"Let's talk to her." Marshall said. "We can't just kill her. If we do we go to jail. So we need to talk to her and figure it out from there."

She nodded got up grabbing Marshall's hand when he got up. They walked downstairs and prepared to face with her mother. Her mother was laying on the couch wearing a small nightgown. "What do you want?" she asked.

Her mother got up and said, "Why Fionna I just want to see my daughter."

"Stop being manipulative. You don't know me. You don't care." she said, bitterness filling her voice. "So tell me, what do you want."

"I need help." Martha said. "Some people are after me and you're all I have." She looked annoyed. "Friday they are coming and I need you to make up your mind and help me."

"I'll give you an answer tomorrow, but for now get out." she replied. Martha rolled her eyes and grabbed her stuff.

"See you tomorrow." Martha said as she left the treehouse. She sat down on the couch trying to figure out what to do about her mother. Marshall sat next to her and she put her head on his shoulder.

"Are we going to help her?" Marshall asked.

"I don't know." she replied. She really didn't. Logically she should help her, but after the way her mother had treated her she really shouldn't.

"I think you should help her. You're a good person and good people help each other no matter what, but it's your choice." Marshall said. Now that she thought about it she knew Marshall was right. She knew what she had to do.


End file.
